Milking-machine pulsator



y 936. c. H. HAPGOOD I 2,039,958

MILKING MACHINE PULSATOR -Filed May 24, 1932 //VI E/V7'0/? ATTOR/VEVJ;

Patented May 5, 1936 UNITED STATES PATENT OFFICE MILKING-MACHINEPULSATOR Cyrus Howard Hapgood, Nutley, N. J assignor to The De LavalSeparator Company, New York, N. Y., a corporation of New JerseyApplication May 24, v1932, Serial No. 613,219

4 Claims. (Cl. 3161) The object of the invention is to provide an of abracket 1 supported in any manner in a inexpensive but efficient milkingmachine pulfixed position. sator. Another object of the invention is toin- Surrounding the sleeve e and abutting against sure the connection ofthe inflation .chambers the face of the .main frame of the bracket 7 ofthe teat cups with pneumatic pressureand exis a valve block g, which isheld in fixed relation haust for predetermined time intervals, whichwith the bracket by means of a set screw it will ordinarily be equaltime intervals. extending through the valve block g and abutting Apreferred embodiment of the invention is against the sleeves. shown inthe drawing, wherein One face of the valve block g forms. a seat 10 Fig.1 is a front view of my invention, shown for a disc-shaped valve 2'turnable on the sleeve 10 with the front cap removed. 6 and havingv ahollow hub 70 which is keyed to Fig. 2 is a side View, principally incentral secthe motel Shaft 17 y means of a driving D ti A valve cap n isscrewed onto the end of the Fig. 3 is section on line 3 Figure 2 showinghollow hub 70 and forms an end closure therefor th fac of th valve seatto enclose and protect the bearings and driving Fig. 4 is a section online 4, Figure 2, showing conhectioht face of the valve Secured to thevalvecasing gis a vacuum tube The specific pulsator shown in the drawingand 0, which is Connected with e of P t a hereinafter described isintended for use in that vacuum and communicates with a p n n .20 systemof milking wherein the inflation chamthe face of the valve easing ut gthe 20 bars of two of a set of four teat cups are con- Valve Seat TheValve easing g iS so p ov ded nected with a source of relativelyhighabsolute i an air pulsation port 0 necting (for pneumatic pressure(conveniently the atmosexample) with tube 2| communicating with phere)while simultaneously the inflation chamthe pulsation chambers of w te tcups of a 28 bers .of the other two teat cups are connected Set, and Wan air pulsation, p t 3|! conwith a source of relatively low absolutepneuhectihg (for example) with a tube eemmuhimatic pressure (say 15inches mercury absolute), eating with the pulsation Chambers o e ot erthe connections being then reversed 'and so on two teat cups o a The twoports are alternately. The specific pulsator shown and deapart InsteadOf connecting the air p ts 0 -30 scribed is also applicable to a .systemwherein and 39 direct with the pulsation Chambers Of the -30 theinflation chambers of one set of teat cups teeyt cups, one p y be O dand the other are connected with high pressure while the in- P y beconnected with the V ve C amber fiation chambers of another set of teatcups are of a Claw, the Operation of the Valve in t s Chamconnected withlow pressure, the connections beher being t olled by the pneumpulsations ing then reversed and so on a1ternate1y The communicated.through Such port, the valve propulsator shown and described may besomewhat dueihg pulsations in the pulsation ambers of simplified if itis desired to operate only a single the tent cups; this principle of t con beset of teat cups and to connect the inflation ihg Shown in theLeitch Patent 1,255,186, chambers of all the teat cups simultaneouslyFebruary 5, 1918- one of the Ports in and El it) ith high or lowpressure, or to pulsat may be omitted and the other connected with allondary (claw) pulsator which controls the teat the pulsation Chambers ofa Set of teat cupseuppmsatione Various other connections may beestablished in I have found it feasible to operate my improved te withi'mown imikmg systemspulsator by means of that simplified and inex ValveZ is provided with two arcuate recesses 545 pensive type ofvacuum-operated oscillating mo- H and The recesses are Pesltlehed 1n DDtor which is utilized to operate oscillating wind- Site half circles 0fthe Valve a c is of a shield'wipers with which automobiles arecustomlength Suiiieiehtly shorter the11 ite nable arily equipped. Thistype of motor i well the ends of both recesses, when the valve is inknown commercial type and is not only about neutral position, to clearthe ports 20 and 30. 550 the most inexpensive type of motor on the mar-One of the recesses (l2) communicates with a ket, but the power requiredto operate it is very port l3 open to the atmosphere.

slight. In the pulsator shown in the drawing, When the motor is operatedit oscillates the such 'a motor a has a shaft b, which turns in valve 2through an arc of about 140, or about a sleeve bearing a, which, bymeans of a lock 70 in each direction beyond the neutral posi- $5 nut d,is held in fixed relationwith a sleeve e tion shown. Assume that thevalve is first turned in a clockwise direction 70 from the neutralposition shown and is then reversed to turn in an anti-clockwisedirection then in a clockwise direction 140 and so on. During eachcomplete clockwise movement of the valve, port 20 is connected, throughrecess I2 and port [3 with the atmosphere during a half, or 70, turn ofthe valve, and is then connected, through recess II and port Ill, withvacuum during the other half turn of the valve; During eachanti-clockwise movement of the valve, port 20 remains con:-'

nected, through recess II and port [0, with vacuum during the first halfturn of the valve, and is then connected, through recess I2 and port [3,with the atmosphere during the other half turn of the valve. If themilking system is one wherein port 30 is utilized, this port isconnected with atmosphere while port 20 is connected with vacuum, andvice versa.

One objection to the use of a motor of the type described for producingpneumatic pulsations in a milking machine is that the motor cannot bedepended upon to oscillate in opposite directions during equal timeintervals. Usually it turns in one direction faster than in the otherand the difference in the two time intervals is uncertain. However, inthe construction comprising my invention, this uncertain irregularity ofthe operation of the motor does not result in any difference in thedurations of the high pressure and low pressure pulsations througheither port 20 or 39. 'Assuming that the speed is greater in theclockwise movement of the valve than in its anti-clockwise movement, itis clear that port 20 will connect with the air port l3 during a slowhalf anti-clockwise turn of thelvalve and then during a rapid clockwisehalf turn of the valve, and will connect with the vacuum port I0 througha rapid clockwise half turn of the valve and then through a slowanti-clockwise half turn of the valve. Thus the time intervals ofconnection of pulsation port 20 with vacuum and atmosphere will beequal, regardless of the inequality in the speed of the valve whileturning in opposite directions. This operation, of course, applies toport 30, if such a port be used; and the high pressure intervals of bothports 20 and 30 will be the same, and the low pressure intervals of bothports will bethe same. 7

The valve block may be integral with the bracket; but since the hole forthe driving pin m may not be definitely positioned in the motor, it isdesirable, if not necessary, that the valve block be adjustable in acircumferential direction so as to properly position the valve blockrelative to the valve. 1

It is sometimes desirable not to equalize the periods of connection ofthe pulsation port with high pressure and with low pressure, but toprovide, for example, for a relatively long high' pressure period and arelatively short low pressure period. This result may be readilyaccomplished by the adjustment of the valve block g by loosening andtightening the set-screw h.

What I claim and desire to protect by Letters Patent is:

1. A pulsator for milking machines comprising an oscillating motor, anoscillating valve connected to and operated by the motor, a valve blockhaving a valve seat and provided with a vacuum port opening in the valveseat, the valve having two opposite arcuate recesses one of whichconstantly communicates with only said vacuum port, the pulsator havingan air port, the other recess being in constant communication with onlythe air port, the valve block having a pulsation port so positioned thatit registers with one valve recess during the latter part of themovement of the valve in one direction and during the first part of themovement of the valve in the other direction, while it registers withthe other valve recess during-the latter part of the movement of thevalve in the last named direction and during the first part of themovement of the valve in the first named direction, whereby the timeintervals of high and low pressure pneumatic pulsation may be definitelypredetermined regardless of inequality in the two semi-oscillatoryperiods of the motor and valve.

2. A pulsator for milking machines comprising an oscillating motor, anoscillating valve connected to and operated by the motor, a valve blockhaving a valve seat and provided with a vacuum port opening in the valveseat, the valve having two opposite arcuate recesses one of whichconstantly communicates with only said vacuum port, the pulsator havingan air port, the other recess being in constant communication with onlythe air port, the valve block havingtwo pulsation ports positionedapproximately apart and each adapted, at each movement of the valve inone direction, to connect first with one recess and then with the otherrecess and at each movement of the valve in the reverse direction tomaintain connection with the second recess and then re-establishconnection with the first recess, the specified positions of thepulsation ports being such that while one pulsation port connects withone recess the other pulsation port connects with the other recess.

3. A pulsator for milking machines comprising an oscillating motor and avalve driven by the motor and partaking of its oscillations, a, valveblock provided with a pulsation port, said pulsator also having a vacuumport and an air admission port, the valve having passages in constantcommunication with only, the vacuum port and air admission portrespectively and adapted to connect the pulsation port alternately withthe vacuum port and with the air admission port and, at a definite placealong each oscillatory stroke of the valve, to reverse said connection,and means to adjust the valve block in a circumferential direction topredetermine the place along each oscillatory stroke of the valve atwhich said connection is reversed.

4. A pulsator for milking machines which comprises an oscillating motor,an oscillatory valve driven by the motor and partaking of its oscil-Vlations, a valve block, a pulsation port, a vacuum port and an airadmission port, the valve having arcuate passages in constantcommunication with only the vacuum port and air admission portrespectively, said passages being .so positioned relative to saidpulsation port that during the movement of the valve in each directionone passage continuously communicates with the pulsation port throughouta definite part of the arc traversed by the valve in each direction andthe other passage continuously communicates with the pulsation portthroughout substantially the remaining part of the arc traversed by thevalve in each direction, whereby differences in the time intervals ofopposite movements of the motor and Valve do not afiect the duration ofthe high pressure and low pressure pulsations through the pulsation.port.

CYRUS HOWARD HAPGOOD.

